As I understand it, any browser on iPhone has to be built on WebKit, so even if you install fire fox or chrome, it’s running on a totally different web engine than the desktop version. Making them more safari re-skins in the same way that stuff like brave or opera are just chrome reskins.
Any Linux distribution should work on AMD CPUs, well, Debian based distros can sometimes have issues with particularly new hardware due to the long time between releases. But bazzite is fedora based so you should be fine with anything.
Nvidia GPUs work just fine with AMD CPUs.
Realistically the question is how high end of a CPU do you want, the mid to high end range AMD CPUs tend to be cheaper than their intel equivalents, but the highest end intel chips edge out the highest end AMD chips right now. Realistically, that won’t matter unless you are doing something super CPU intensive and just want the most power possible for your machine.
AMD CPUs also have better integrated graphics, not super important if you have a dedicated GPU, but, there are times when having a second somewhat capable graphics processor could be useful.